Whooping cough can cause serious disease, particularly in young infants. It is recommended that pregnant women receive the whooping cough vaccine to protect mothers and infants against whooping cough. There are however concerns that high levels of maternal antibody in the infant at birth may prevent the infant from producing such a good response to later vaccinations. There is a type of blood cell in the circulation called T cells which are important for both antibody production and protection against disease. In his pump-priming project 'Elucidating the effect of maternal immunisation on the subsequent development of T cell response following pertussis vaccination in infants,' Qibo Zhang from the University of Liverpool and his team studied infant samples from Thailand to determine whether the infants' T cellular response including cytokine responses to vaccination is affected by maternal immunisation during pregnancy in collaboration with partners in Thailand.

The results show that maternal immunisation has significant effect on infant T cell responses to vaccination, and there are also major differences in the T cell responses between children immunised with two different type of whooping cough vaccines. These effects and differences in T cell responses in infants may have significant impact on the infant's antibody response and protective immunity. Information on the impact of maternal immunisation on infant immune reponses will be instrumental in the decision making in many LMIC countries whether or not to implement the strategy of maternal immunisation.

The results from this project and follow-up studies do not only reveal the possible blunting effect by maternal antibodies but also the impact on the T cell immunity in infants and older children. The information may not only impact on decision making on infant immunisation against whooping cough but also on paediatric vaccination against other infections.